Automatic on and off control system for gas plants



June 2, 1953 c. M sPoRRAN ETAL 2,640,768

AUTOMATIC ON AND OFF CONTROL SYSTEM FOR GAS PLANTS Filed June 25, 1948 5 Sheets-Sheet 1 JNVENTOR) CHARLES MACSPORRAN & owEN GARRETSON BwQmL ATTORNEYS June 2, 1953 c. M sPoRRAN EI'AL 2,640,768

AUTOMATIC ON AND OFF CONTROL SYSTEM FOR GAS PLANTS Filed June 25, 1948 5 Sheets-Sheet 2 INVENTORS CHARLES MAc SPORRAN & OWEN L. GARRETSON ATTORNEYS June 2, 1953 c. M sPoRRAN ETAL 2,640,768

AUTOMATIC ON AND OFF CONTROL SYSTEM FOR GAS PLANT-S Filed June 25, 1948 5. Sheets-Sheet 3 INVENTORS CHARLES MAC SPORRAN & OWEN 'L. GARRETSON BY BM QQAL ATTORNEYS June 2, 1953 c. M SPORRAN ETAL 2,640,768

AUTOMATIC ON AND OFF CONTROL SYSTEM FOR GAS PLANTS Filed June 25, 1948 5 Sheets-Sheet 4 i IN V EN TORS' CHARLES MACSPOQRAN& OWEN L. GARRETSON BY DQi +QQJ ATTORNEYS J ne 2,1953 c. MacsPoRRAN Em 2,640,768

AUTOMATIC ON AND OFF CONTROL SYSTEM FOR GAS PLANTS Filed June 25, 1948 5 Sheets-Sheet 5 INVENTOR) CHARLES MACSPOR RAN &

OWEN L. GARRETSON ATTORNEYS the attached drawings.

Patented June 2, 1953 AUTOMATIC ON AND OFF CONTROL SYSTEM FOR GAS PLANTS Charles MacSporran, Bartlesville, kla.,

and

Owen L. Garretson, Roswell, N. Mex., assignors to Phillips Petroleum Company, a corporation of Delaware Application June 25, 1948, Serial No. 35,116

3 Claims. (01. 48-190) This invention comprises automatic systems for supplementing the supply of gas to a gas holder.

"Under present day economic conditions it has been found to be better practice to introduce gas from a supplementary or stand-by source into the gas supply system of a city to carry intermittent heavy loads rather than increase the gas manufacturing capacity of the system. The usual practice is to introduce a light hydrocarbon gas such as butane or propane directly into the gas holder of the system from a stand-by storage tank or tanks of sufficient capacity for the purpose. As the B. t. u. value of the supplementary gas used'is considerably higher than that of manufactured gas, it is also the usual practice to dilute the butane or propane with'air, preferably at the time of delivery into the gas holder. Admixture of air with the butane'or propane is accomplished by the use of inspirators which serve to draw air into the system and admix it with the gas at the time of its delivery to the gas holder. This invention is concerned with such systems.

One of the objects of the invention is to provide an automatically operating on and oil control system for supplying air diluted gas to the gas holder of a city gas system under the control of the movement of the gas holder. v

A more specific object of this invention is to provide a hydraulic system for this purpose. I

'system by the movement of the gas holder which results from the withdrawal of gas therefrom and the supply of gas thereto. 7

Still another object of the invention is to provide a system of either type by means of which two or more gas supply systems are caused to be successively placed in operation under loads so heavy that the actuation of one inspirator system is inadequate and the supply of supplementary gas by means of one or more additional inspirator systems is required.

Other and more detailed objects'of the invention will be apparent from the within disclosure of the several embodiments thereof illustrated in In the accompanying drawing Figure 1 is a diagrammatic and schematic illustration of a hydraulically actuated control system in accordance with this invention for effecting the operation of two inspirators successively when conditions require;

Figure 2 is aside elevational view with parts broken away of the gas holder'actuated control mechanism for this system; g Figure 3 is 'a front elevational View thereof;

Figure 4.- is an' enlarged side elevational-fragmentary view of the hydraulic mechanism used in the system of Figure 1;

Figure 5 is a side elevational view with some parts in cross-section of an electric switch actuating mechanism for the system of Figure 10;

Figures 6, '7 and 8 are diagrammatic illustrations of the various control positions of the actuatingmechanism forthe system of Figure 1;

Figure 9 is a detailed perspective view with some parts broken away of the cable weight actuator for the system of Figure 1; 1 1

"Figure, 10 is a schematic and diagrammatic illustration of an electric system in accordance 'with'tliis'invention adapted to the successive control of two inspirators; Figure 11 is a'detailed perspective view of the starting member for the cable actuated support for the hydraulic cylinders of the system of Figure 1; and r Figure '12 is a detailed elevational cross-sectional 'view of the mounting for one of the hydraulic cylinders of the system of Figure 1.

A complete hydraulically actuated system in accordance with this invention employing two inspirators is illustrated in Figure 1. The gas holder, which is sometimes called a gasometer, as illustrated, consists of a surrounding supporting an d guiding framework I, a fixed container bottom-section 2, and a' pair of vertically movable top sections 3 and 3& It is well understood, of course, that the upper sections 3 and 3 are arranged forvertical telescoping movement with respect to each-other'and the bottom section 2, and are" adapted for downward movement as the gas stored within the holder is withdrawn and upward movement .as it is replenished.

"These elementsare only diagrammatically illustrated as details of the 'gasometer form no part of this invention. In the system of Figure -1'the top holder section 3 is provided with the vertical supporting bar 4 bolted thereto as shown. Secured to the lower end of bar 4 by meansof a reinforcing gusset plate 4 is a cross arm 4 to which is attached a plate 4 having a guide for sliding engagement with the framework I (see Figs. 2 and 3).

Attached to the framework 1 by means of a clamp 45 are a pair of yokes l1 and H in which are rotatably supported the sheaves 48 and 48'. Near the lower end of the framework l are clamped the bracketed tubular housings 55 (see Fig. 11) providing pivotal supportsiorntubular members .52 "and 52. Rotatably and vertically slidably mounted in the tubular housings 55 are the tubes 55 (see Fig. 4) on the upper end of which are pivotally mounted at 54 the tubular supporting members 52 and 52. The lllper ends of the tubular housings are each provide'd'witna pair of adjustable set screws 55 for limitingpivotal rotation of the members 52 and -52 on the pivotal supports 55. The provision er .thetubes 55' within the tubular casings 55 permits vertical sliding movement thereof .so. that in the event of the tipping of the gas holder under high wind pressures to the right (Fig.2) ithese assemblies can move upwardly, thus insuring against the breakage of the cables which areattached to the members 52 and 52'. It will be understood by reference toFigure3,'that-. one of these assemblies isattachedto each sidesof the columnl by-bolts which engage-the brackets of each housing 55. Cables! and 49' are looped over the sheaves 48 and 48. and theirrespective ends are .pivotally. attached to the members 52 and 52' respectively by means of theshackles SI and 5|.

Tubular members 52 have the .same constructionin. this form of theL syStem-as they do in.- the electrical system, and as clearly illustrated Figure 5. They each consist of a short length" of pipe closed attheends bymeansotpipe caps and have therein a weight,..as in thecase-of the weight I52 which mayslidetromone-end .ofthe tubular housing tothe other asit tiltsbackand iorth. .If desired the cylinder thusiormed may contain a light viscousiiuid-such-as 'a mineral oil and'the relative size .of theweight L52 with respect to the internal bore of the tube-may be such that the rate of movementoi the weight in the tube can be predetermined. The reason for this construction may as well be described atthis point. These systemsare of the :on-and ofi type, and it will be understood that as-the tubular housing I52 tiltssayfrom the angle-shown in :Figure- 5ubyclockwise rotation so "as to tipiin the opposite direction the weight I52 will move to the other end of the tube .prov-idingwhat iscalled herein -an on :and on .type of action. In .other words, when the tubulanhollslng-tipsa little beyond center in-either direction it iscarried allthe way .in that direction :by the .-.shifting of the weight to the lower end-thereof.

7011810011188 of 1 each of the *cables -.49 and-49' passes through the tubular weights 5ila-nd-i5llfirespectively. These weights -:are constructed :as illustrated in Figure :9, and each includes .a'zsmall- .er tube 58"., secured therein, through'which'. the cable actually passes. "Near the upper end -:o'f reach tubular weight 50 is a fiangefifl which may .reston-the plate 4 (see Fig.12) through "which the tubular weights extend so. asto lie; .in1aperturesftherein. These weights-are'free to'..-move up and down in the plate 4* :but-their downward movement is limited by the flanges =50 (Fig.9).

The :same course of:eac'h of the cables hasrat- -tached thereto adjustable collars. In the. case of Pivotall-ysuspended from the longitudinal: rib

52 by means of which the tubular members 52 and 52 are pivotally supported are a pair of hydraulic cylinders III and I2. The rib 52 is provided with a series of holes equally spaced on opposite sides of the pivot-point 54 so that the hydraulicvcylinders 'I (l and. I 2. can beattached thereto at different radial points. The cylinders i0 and I2 are provided with flexible hose connections 43 and 44 respectively. Each of these cylinders is adapte'd tocontain a liquid of suitable characteristics, as for example a mineral oil. As illustrated .in Figure .l2,. in the case of cylinder Ill, bothtcylinders Ill and I2 are provided with a vent IIl'iso' that trappedair may move into and out of the cylinder "as'the fluid flows thereinto and therefrom ina manner to be described.

To insure clarity, it will be noted that the system illustrated in these figures comprises two exactly duplicated sets ofimechanism because it is intended tov illustratein the. complete systemhow the sequential operation of twoinspiratorsmay be efiected. "It will be understood, of course,.that when only .one inspirator .is employed that .only one of these actuator systems will be necessary. The complete system for. one inspirator is shown in .Figure .1, it being understood, as suggested above, that the apparatus within therectangle will be duplicated for the actuator directly in back of that which appears in Figureil and which is shown on theleft in'Figure 3.

'Therpropane or butane gas is supplied from suitablestorage tanks,.not.shown, through the lines It and I4 at a pressure, for example, of 30.110 .40 pounds per. square.inch. Pipe I4 ;connects directly to the inlet side of thenormally closed .valve and is provided with a pressure gauge 'YIG. lTheioutlet .side of valve I5 is vconnectedby pipe I8 which includes a control valve 2] .anda. pressuregauge. 22 to .the intake side of the'inspirator I9. The discharge connection .of theinspirator is connected bya line '25 tothe gasmain. I3 whichconnects thegas holder with the'gas distributing system. Supplementarygas supply line .lllis provided with a branch "251.comtaining a control valve26, a pressure regulator orreducing valve 2'1, and serves to connect line I4 with the intake side of the normally closed valve28. The output side of this valve is connected tothe input side of the normally open valveil33. The pipes 25 and 38 are provided with thepressureigaugesiS and $35,1as shown. .Pipe 50 is provided with a branch 31 which connects to a pressure fluid operated motor .32 and .for actuating .the valve .I5.. This motor may conveniently be of the diaphragm type. 'The outputxside-of valve 33 isconnected .bymeans of a line'34 to the line 25 and includes thepressure gauge. andthecontrol valve .31. Valves28 and-33 .are actuated by means of pressure fluid operated motors AI andAZ whichalso may conveniently-be .ofthe diaphragm type. The housings for these motors are provided with connections to opposite sides of the diaphragms and hydraulic cylinder IIlis. connected by means of the flexible hose 43 to the pipe 39 having branches which .connect .to the motors and 52 on the topsides of the diaphragmsthereof. Similarly thehydraulic cylinder I2 is connected by means of the flexible hose 44 to the pipe 38,-which also has branches connecting to. the hoses of motors III-land on the lowersides of the diaphragms thereof. .The hydraulic cylinders corresponding .to. the cylinders I-iland 12, one of which, namely .cy-linder --I-2' appears in Figure 3, are similarly connected by flexible. hoses to'thelines39' and 5 38' to the control apparatus in the upper rectangle of Figure 1, which is exactly the same as that delineated within the lower rectangle. The supplementary gas is supplied from the upper system by means of line 20" to the gas main l3 as diagrammatically illustrated.

Before describing the operation of this system it is first to be noted that valve I5 is normally kept closed by means of spring loading and is arranged to open by movement of the valve disc downwardly from its seat when pressure is applied to the motor 32. Valve 28 is similarly constructed. On the other hand, valve 33 being normally open is loaded with a spring to hold the valve off its seat, which valve will move onto its seat when pressure fluid is supplied to the top side of the diaphragm of motor 42. It will be noted that in the position of the parts shown in Figure 1, which corresponds to the diagrammatic view of Figure 7, both cylinders l and the corresponding cylinder lfl, not shown, are in their upper position so that the fluid pressure in the line 39 is greater than the fluid pressure in line 38. The result is that normally closed valve 28 is open and normally open valve 33 is closed. As valve 28 is opened pressure fluid comprising supplementary gas supplied through the branch 25 is supplied to the motor 32 through the branch 3| at some suitably lower pressure than the pressure in line l4 by reason of the action of pressure regulator 21. The supply of pressure fluid to the top side of the diaphragm of motor 32 causes valve IE to open so that supplementary gas is supplied through line l4, valve I 5, and line 18 to the inspirator [9. The movement of the gas through this inspirator draws air thereinto for admixture with the gas, which mixture is delivered by line 20 to the main l3, valve 38 of course being open, as well as valve 2!.

As the corresponding control equipment in back of that appearing in Figure 1, that is the equipment at the left of Figure 3, is also in the same position as that shown in Figure 1, the system diagrammatically illustrated by the upper rectangle of Figure 1 is similarly in operation so that additional supplementary gas is supplied from the tanks through line [4' to line 23' and thence to the gas main 13. An inspirator for this second system admixes air with the supplementary gas so that the mixture of gas and air being supplied to line l3 through the connections 20 and 20' is substantially the same.

Figure 7 diagrammatically illustrates the positions of the cylinders 52 and 52 and the weights 50 and 50 with relation to the collars on the respective cables 49 and 49' so that simultaneous operation of both inspirator systems is thus effected.

Assuming that the supply of supplementary gas together with the normal supply of manu: factured gas to the gas holder is at a rate greater than gas being withdrawn from the gas holder, it is apparent that the movable sections 3 and 3 will gradually rise. The upward movement of these sections will carry with them the weight controlling structure 4 4 and 4, so that when these parts have moved to the position shown in Figure 3 both weights 5! and 59 will be resting on the bar 4 and their upper ends will be approaching the collars 49 and 49 on the cables 49 and 49 respectively. When the gas holder moves into full position the upper ends of the weights 5!) and 50 will engage the collars 48 and 49 to tip the control cylinders 52' and 52 from the position shown in Figures 2 and 3 to 6 the position shown in Figure 8, cutting off both inspirator systems simultaneously. The hydraulic cylinders l2 and i2 will be above the level of the hydraulic cylinders l0 and 10. As a result the pressure in lines 38' and 38 will be higher than the pressure in lines 39 and 39. It follows that the valve 28 for the lower system (Fig. 1) and the corresponding valve of the upper system (not shown) will be closed, and valve 33 and the corresponding valve of the upper system (not shown) will be open. The opening of valve 33 and the similar valve of the upper system will exhaust fluid pressure from motor 32 and the corresponding motor of the upper system (not shown) through branch 3| to line 30, through valve 33, pipe 34 and open valve 31 to line 20 and correspondingly through similar elements of the upper system through line 20'. Thus the small quantity of supplementary gas used as the pressure fluid for actuating the motor 32 and the corresponding motor of the upper system (not shown) will exhaust into line i3 through the lines 20 and 20" respectively rather than into the atmosphere, thereby eliminating all possible fire or explosion hazard.

To simplify the description, since the parts of the upper system of Figure 1 (not shown) are exactly like those of the lower system, the following description of the lower system will be taken as also representing the description of the upper system. The exhausting of motor 32 will permit valve I 5 to close cutting off the supply of supplementary gas through the line 20 to the manifold l3, and of course, through the line 20'.

When the withdrawal of gas from the gas holder through the line I3 exceeds the rate at which it is normally being supplied from the gas manufacturing plant, the movable sections of the holder will begin to descend, of course carrying all of the parts suspended therefrom by the structure 4 and 4*. Referring to Figure 8, it will be seen thatsince the collar 49 is at a higher level than the collar 49 should the gasholder sections continue to fall ultimately the weight 50' will engage the collar 49 and tip the control cylinder 52 to the position shown in Figure 6, control cylinder 52 remaining in the position shown. As a result the pressure in line 39' will be higher than the pressure in 38', so that the upper inspirator system of Figure 1 will be put into operation.

The details of setting this system into operation so that supplementary gas is supplied from line I4 through the associated inspirator and line 20' into the main [3 and thence to the gasholder will be apparent from the following description of the details of setting the second inspirator system into operation which occurs if the movable sections of the gasholder continue to descend, notwithstanding the supply of supplementary gas by'means of the upper inspirator system. In other words, if gas is being withdrawn from the gasholder faster than it is supplied from the manufacturing plant as supplemented by the upper inspirator system, the movable sections will continue to fall until the weight 50 engages the collar 49 whereupon the control cylinder 52 will be tipped to the position shown in Figure 7. As a result hydraulic cylinder II] will be higher than cylinder l2 and the pressure in line 39 will be higher than the pressure in line 38, putting the lower inspirator system of Figure 1 in operation. This results because normally closed valve 28 will open and normally open valve 33 will close, from which accuses:

ittfoll'ows: that: gas under pressure-will. be -suD-' plied from line I4. through: hand valve 26, pressurereducingvalve 27, line25r, valve 218.. line 30- and branch 3I to motor 321 of valve t5, which being normally closed upon energization opens. The opening of valve I5 will supply supplementary gas from line I4 through valve I5, manual valve- II and line I8 to the inspirator I9. The supplementary gas in passing through the inspirator It will pick up and admix therewith air which is. discharged through valve 33 and line 20. into the main I3 and thence into the gasholder.

Assuming that the system is properly designed so that the total supply of supplementary gas through the two inspirator systems to the gasholder is adequate in conjunction with the gas being supplied from the manufacturing plant to overcome the maximum drain on the gasholder it is apparent that the gasholder sections will now begin to rise and will carry with. it the parts supported by the members 4 and A so that ultimately the system. will return to the position shown in Figure 3, and then: finally move to the position shown in Figure 8, at which time. both inspirator systems are shut ofi simultaneously.

It seems hardly necessary to note that the additional movement of the bracket I and connected parts from. the position shown in Figure 6 to the position shown in Figure 7 is possible because the weight 5.0 will rest on the collar 19 as the bracket 4 descends to the position shown in Figure 7 to tip the; control cylinder 52 into the position. shown in Figure 7.. This has. been diagrammatically illustrated. by the disconnection of the-crossj-bard from the weight 5.0 (see Fig. '7).

It will, of. course, be understood that. in installations-where more: than one inspirator will. not be. required that the same; system may be employed, but itcan be, simplified by the: e1imina-.. tion of; the second inspirator and associated equipment and controls therefor. Likewise, where it is anticipated that more than. two inspirator systems are required it will be possible to duplicate the apparatus to provide three or four additional supplementary gas inspiratorsystems, a condition however, which is not likely to Qccurbecause, by; proper design. no more than two inspiratorsystems will be. necessary to provide the required supplementary gas capacity.

The electrical system is generally similar to. the hydraulic system just described with some modification, as illustrated. in Figures 5 and. 1.0. In the electrical system the pivotally mounted cylinders I52 and I52" corresponding to the cylinders'SZ and 5,2" are provided; hutin: this case there is mounted on these cylinders the mercury switches I40 and I40. A double inspirator system is shown in Figure 10, and is modified sufficiently to adapt it to electrical operation. In this-case the pressure fluid operated valve 28 in each inspirator system is substituted by a valve 28 which is electro-magnetically operated by means of an, electric motor such as for example the solenoid motor 28". Valve 28* is normally closed as is valve I5 In this system there is no need for a valve corresponding to the valve 33 of the hydraulic system. In place thereof there is provided a needle, valve I30 for controlling the rate of pressure fluid exhaust from the motor 32, which as before operates the valve I5. The terminals of the solenoid motor 28 are connected by the wires. I20 to the mercury switch I40 and include acurrent source as illustrated. Similarly, the mercury switch M0 is connected to the solemid motor of the upper inspiratorsystem dia-. grammatically illustrated by a rectangle in, Fin ure: 10, and indicating an exact. duplicate of the apparatus within the lower rectangle. of that. figure. The pivoted cylinders I52 and I52. are operated in exactly the same way as in the previous system by means of the weights which. move with the movable sections of the gasometer, the collars on the cables which operate" there with.

It will be assumed that. the system. asshown in Figure 10 is in the-condition where the movable sections of the gas holderare all the way down and both inspirators are operating. In other words; the cylinders I52 and I52 have been moved to the position shown in Figure l'O'iby the weights as indicated so that both circuits IZII': and IN are energized. Thus both solenoid motors 28 will be energized and botlr valves 28 will be open. As a result pressure fluid from the gas lines It and M is supplied to the motors 32 so that the valves I5- are open. Thus air and supplementary gas in mixture are introduced into the gas distributing system F3- and the gasometer through both of the lines 20" and 20 to supplement the normal supply of manufactured gas to the system. If the rate. of supply exceeds the rate of outgo the movable sections will start upwardly until weight 50" is picked up by the bar 4 so that it moves the weight 50.. When the gasholder is, lull. the weights 53 and 59 will engage the collarsv 4.5 and 49 tipping both cylinders I52" and I52 from the position shown in Figure 10 to a postticn corresponding to. the position of the cy1inders 52' and 52, as illustrated in Figure 8.. Thus the mercury switches I40 and MI] will break the circuits I28 and I2 0 to the solenoid valves of. bothinspirator systems. The eifect of thisv will be described in detail in connection with the lower inspirator system, it being understood that the upper inspirator system is exactly the same: and works in the same way. Thus the opening of circuit I21; will de-energize the solenoid: 28 so that valve 28 will be closed by its spring, it being a normally closed valve biased by a spring to closed position. The closing of valve 28* will cut off the supply of gas from the line I4 to the motor 32 of valve I 5, and the motor 32 will then exhaust through the needle valve I 30, line 34 and valve 2I into line 20,, and from there into line IS. Valve I5 is also of. the nor.- mally closed type, and as soon as its motor 32; is de-energized and exhausted it will close, cut.- ting off the supply of. supplementary gas from line. I I to inspirator I9.

It is believed that the description of the. manner in which the inspirator system. first the. upper inspirator system of Figure 10v and then the lower inspirator system of Figure 10 are: succesively put into operation when the gas,- ometer sections 4 under conditions where the. withdrawal of gas from the gasholder through the main exceeds the supply of gas to the gasholder from the manufacturing plant, will be apparent. Briefly, the tipping of cylinder I52 which occurs first will close the circuit I20 at mercury switch I SII', setting the upper supplementary gas system into operation to supply supplementary gas from. line It to line 28'. Should the gasholder sec tions continue to fall cylinder I52 will be. tipped to cause mercury switch I40 to close circuit I20: and put the lower inspirator system into opera- 9 tionby opening valve 28 so that gas is supplied from the supplementary line M to line 20.

It will be understood that in all forms of the system herein disclosed the pressure fluid for operating the motors 32 may be compressed air supplied from auxiliary equipment in which case the exhaust lines 30 may open to the atmosphere as there would be no hazard in discharging the engines 32 to atmosphere. It is also tobe noted that the needle valves I30 could be substituted by orifices of the proper capacity to permit operation of the motors 32 as required to get the desired results of this invention.

It is also to be understood that it is contemplated as being within the scope of this-invention to operate the valves of the system of Figure directly by means of electric motors like the solenoid motors 28 which would be arranged to cooperate with the stems of the valves 15. While this simple change would greatly simplify the system, it is not as desirable as the system shown because a considerably more powerful motor would be needed to operate the valves l5.

It is also contemplated to be within this invention to use either the hydraulic or electric systems for operating mechanisms equivalent to the inspirators for supplying the supplementary gas. Thus, for example, the hydraulic or electrical control systems may be used to actuate devices such as blowers or compressors for delivering the supplementary gas from the storage holders to the gasometer and connected mains. Thus there are obviously a number of changes within the skill of those familiar with the art which would be substituted in the light of the disclosure herein, but which would be the equivalent of the systems disclosed, and therefore considered to be within the scope of this disclosure.

It will be understood that the various control valves 2|, 26, 31 and 38 are merely provided for the purpose of isolating the inspirator system for repair and maintenance purposes, and for comolete shut-down under some conditions.

As will also be understood by those skilled in the art the supplementary gas would normally be collected in the storage tanks at a pressure normally above 30 to 40 pounds, the pressure at which it is supplied to the line H, which of course, contemplates the provision of a suitable pressure reducing valve or regulator in the line 14, but not shown as it is not essential to operativeness.

It is within the scope of this invention employing either of the systems here disclosed, to supply all of the gas to the gasholder through the inspirator systems, in which case the gas supplied from the source, as for example a gas manufacturing plant, would be delivered to the lines l4 and I4 and under the control of the inspirator systems ultimately into the main l3 and thence to the gasholder or directly into the gasholder. For this reason it is not intended that the use of the words supplementary gas in the claims is to be intended to limit the invention to supplying gas to the gasholders from an auxiliary source to supplement the supply of gas to the gasholders from a gas manufacturing plant. It is intended that all of the claims in this case cover systems where all gas supplied from the gasholder goes through one or more inspirator systems as well as cases where gas is supplied through one or more inspirator systems to supplement the supply of gas from a main source Such as a gas manufacturing plant.

10 In view of the foregoing we do not desire to be limited to the particular embodiments herein disclosed, but rather as required by the scope of the claims granted us.

What is claimed is:

1. In a gas supply system; the combination comprising a variable volume'gas holder normally supplied from a primary gas source, said gasholder including a top section movable vertically with changes in the volume of gas contained therein, a first conduit connecting a sup-' plementary gas supply to said holder, a first control valve in said first conduit, 9. second conduit connecting a supplementary gas supply to said holder, a second control valve in said second conduit, a first pulley mounted adjacent said gas holder, a cable carried by said pulley, a pivoted member carried by said cable and adapted to assume afirst position upon movement of said cable in one direction and a second position upon movement of said cable in the opposite direction, a second pulley mounted adjacent said gas holder, a cable carried by said second pulley, a pivoted member carried by said second cable and adapted to assume a first position upon movement of said cable in one direction and a second position upon movement of said cable in the opposite direction, means carried by the movable section of said gas holder adapted to cause movement of said first cable in one direction upon downward movement of said gas holder to a predetermined point and adapted to cause movement of said second cable in the same direction upon further downward movement of said gas holder, said last means also adapted to cause simultaneous movement of said cables in the opposite direction upon movement of said movable section to the full position of said gas holder, and valve actuating means responsive to the positions of said pivoted members whereby said control valves are opened upon movement of said pivoted members to said first positions and closed upon movement of said pivoted members to said second position.

2. In a gas supply system, the combination comprising a variable volume gas holder normally supplied from a primary generating source, said gas holder including a top section movable vertically with changes in the volume of gas stored therein, conduit means connected to said holder for supplying supplementary gas thereto and hydraulically operated control valves actuated by said movable section for rendering said supplementary gas supply means operative in successive stages to supply supplementary gas at two different rates to said gas holder under conditions of heavy gas demand on said gas holder, said valves being also actuated by said movable section to render said supplementary supply means inoperative when the volume of gas in said1 gas holder is restored to a predetermined eve 3. In a gas storage and supply system, the combmation comprising a gas holder having a movable section responsive by ver-tica1 displacement to the volume of gas contained therein, said gas holder being connected to a gas distribution system and also being normally supplied with gas from a principal gas generating source, a supplementary source of gas, conduit means connecting said supplementary source to said gas holder, said conduit means including therein fluid operated control valves, cable suspended weights 1 1 12 carried by said "gas holder linking said control References Cited in the z-file of this patent valves to the movable section of said gas holder, UNITED STATES PATENTS a hydraulic pressure actuated system responsive in successive stages to displacement of said Number Name Date weights to actuate said control valves to open 5 427,832 Burrows May 13,1890 them successively upon downward movement of 1451011 Drefi e1n said movable section to vpass a supply of gas from 1,931,791 Duermger 24, 1933 said supplementary source toi'said gas holder, and 1,944,969 Deans 1934 upon upward movement to interrupt the supply 235L636 Robb at 5,1941 2,402,522 Bucknam June 18, 1946 of gas thereto when a predetermined volume has 10 been restored to said holder. OTHER REFERENCES Chemical Abstracts, vol. 39, page '2393 (1945). Abstract of article by Anderson appearing in Gas," vol. 21, No. 4,.pages '2 4-28 (1945).

CHARLES MACSPORRAN. OWEN L. GARRETSON. 

1. IN A GAS SUPPLY SYSTEM, THE COMBINATION COMPRISING A VARIABLE VOLUME GAS HOLDER NORMALLY SUPPLIED FROM A PRIMARY GAS SOURCE, SAID GAS HOLDER INCLUDING A TOP SECTION MOVABLE VERTICALLY WITH CHANGES IN THE VOLUME OF GAS CONTAINED THEREIN, A FIRST CONDUIT CONNECTING A SUPPLEMENTARY GAS SUPPLY TO SAID HOLDER, A FIRST CONTROLED VALVE IN SAID FIRST CONDUIT, A SECOND CONDUIT CONNECTING A SUPPLEMENTARY GAS SUPPLY TO SAID HOLDER, A SECOND CONTROL VALVE IN SAID SECOND CONDUIT, A FIRST PULLEY MOUNTED ADJACENT SAID GAS HOLDER, A CABLE CARRIED BY SAID PULLEY, A PIVOTED MEMBER CARRIED BY SAID CABLE AND ADAPTED TO ASSUME A FIRST POSITION UPON MOVEMENT OF SAID CABLE IN ONE DIRECTION AND A SECOND POSITION UPON MOVEMENT OF SAID CABLE IN THE OPPOSITE DIRECTION, A SECOND PULLEY MOUNTED ADJACENT SAID GAS HOLDER, A CABLE CARRIED BY SAID SECOND PULLEY A PIVOTED MEMBER CARRIED BY SAID SECOND CABLE AND ADAPTED TO ASSUME A FIRST POSITION UPON MOVEMENT OF SAID CABLE IN ONE DIRETION AND A SECOND POSITION UPON MOVEMENT OF SAID CABLE IN THE OPPOSITE DIRECTION, MEANS CARRIED BY THE MOVABLE SECTION OF SAID GAS HOLDER ADAPTED TO CAUSE MOVEMENT OF SAID FIRST CABLE IN ONE DIRECTION UPON DOWNWARD MOVEMENT OF SAID GAS HOLDER TO A PREDETERMINED POINT AND ADAPTED TO CAUSE MOVEMENT OF SAID SECOND CABLE IN THE SAME DIRECTION UPON FURTHER DOWNWARD MOVEMENT OF SAID GAS HOLDER, SAID LAST MEANS ALSO ADAPTED TO CAUSE SIMULTANEOUS MOVEMENT OF SAID CABLES IN THE OPPOSITE DIRECTION UPON MOVEMENT OF SAID MOVABLE SECTION TO THE FULL POSITION OF SAID GAS HOLDER, AND VALVE ACTUATING MEANS RESPONSIVE TO THE POSITIONS OF SAID PIVOTED MEMBERS WHEREBY SAID CONTROL VALVES ARE OPENED UPON MOVEMENT OF SAID PIVOTED MEMBERS TO SAID FIRST POSITIONS AND CLOSED UPON MOVEMENT OF SAID PIVOTED MEMBERS TO SAID SECOND POSITION. 